Abstract
Production records from 3 flocks of turkeys comprising 2 strains are analysed to determine the heritabilities of, and genetic correlation between, egg production during the 6 weeks following flock attainment of 20 per cent production, and total poult production over 24 weeks of lay. Part record and full record selection are compared, taking into consideration the difference in selection intensity obtainable under the two methods. Practical problems involved in part record selection are discussed and it is concluded that, when, as appears probable in large flocks, neither system exhibits a clear genetic advantage over the other, practical considerations will weigh in favour of full record selection.